Question Quadro P4000 won't SLI pair on SLI ready Board

[marcusmarcula]

For Months I've been trying to get my two Quadro P4000 to SLI Pair with the corresponding SLI Bridge and other different types of SLI Bridges. On the Nvidia website it lists the motherboard I'm using as SLI Ready and even states it as compatible to SLI with the P4000 series. I recently upgraded my PSU and plugged the power cables directly to the GPUs, so not to Daisy Chain them. I put the bridge on the 4 fins marked SLI with the PNY Quadro HB SLI 2 way 3 slot spacing until snug like the instruction directed me. After, installing the latest Nvidia drivers the Bridge would not show up in the Nvidia control panel as being in SLI and even listed it as being disabled in the cards Topology.

1) First I tried to swap the cards from the slots and reattach the bridge again. It still would not show up in the control panel.

2) I uninstalled all Graphics Drivers through DDU and did a fresh install to the latest graphics drivers, which resulted in the same.

3) I messed with the Bios settings to make sure the motherboard would SLI the GPUs, but this did not work either.

4) I checked the device manager and both cards are listed and functional, I even double checked with GPU-Z

5) I literally did the exact same steps as mentioned above with an Engineer at PNY but on Windows 10 OS on my second SSD, but it did not work either.

6) Uninstalled and reinstalled drivers again but this time with advanced settings selected.

7) Disabled Intel Chip-set

8) Strangely enough I had a stock Sli bridge that came with the board that I attached, It was picked up in the control panel, however it said it was insufficient power to SLI the cards and gave me a link to the Nvidia site with the certified motherboards.

9) Tried an ROG HB SLI bridge but would not show in the Nvidia control panel either.

10) Returned the Quadro bridge and currently waiting for them to send a new one when they get more in stock directly from PNY (Not even sure if they make them anymore since Nvidia just started showing RTX and accessories for RTX only on their website.)

At this point I've reached out to Asus, PNY, and Nvidia and none of the m came up with a solution to my issue. Most said it was the bridge itself, but I'm trying different bridges and they do not seem to work either. At this point I'm not even sure if I can really SLI these cards with this board or these cards cannot be paired in general unless its in a certified workstation. I saw a board that Gigabyte has out that claims is SLI 2-way with Quadros but it is not even listed on Nvidias website.

I'm not sure what else to do, I've invested a lot of time and effort trouble shooting this, but I'm at a loss for how I should proceed from here. I would greatly Appreciate any help from anyone who knows more about the cards or sli in general. I also am suspicious because I'm using 6 monitors (3 in each card) and I think this also might be affecting the power draw to the cards and preventing them from communicating.

Here are my specs with some screen shots, I look forward to hearing from someone with an idea of what to do in this situation.

Product Model & S/N:	ASUS SABERTOOTH Z77 MT7025K16300992
BIOS/FW Version	American Megatrends Inc. 2104
CPU:	Intel® Core™ i7-3770k @ 3.50GHz
Memory:	G.Skill Ripjaws X Series 16 gb (8x8) DDR3 1333
HDD:	Samsung Evo 850 SSD 500GB, Samsung Evo 850 SSD 250GB
VGA:	Nvidia Quadro P4000, Nvidia Quadro P4000
Power Supply:	Corsair HX850I
Network/Lan:	Intel® 82579V Gigabit Network Connection
Other Hardware:	Corsair Commander Pro Fan Controller, SABERTOOTH Z77 SLI Bridge, Quadro HB 2-way 3-slot SLI Bridge
OS Version:	Windows 7 Ultimate 6.1.7601 Service Pack 1 Build 7601
Related Driver(s):	Nvidia Graphics 25.21.14.1881, Intel® 7 Series/C216 – 1E02, Intel® HD Graphics 4000

Device Manager

Nvidia Control Panel

Nvidia Topology

Proof of SLI Certified from Nvidia Site

GPU-Z for both Cards

 

[Lutfij]

I think you were given a faulty HB bridge after reading that the stock bridge was able to get you to SLI albeit with less power to the cards. how old is the PSU, mind you?

 

[marcusmarcula]

PSU is literally less than 4 months old. I spoke to Asus engineer and they said the same. Unfortunately I returned the SLI Bridge at this point in time, and the PNY HB SLI for quadros is on back order and restock at the moment. However, I was going to try to pair again with perhaps an Nvidia GTX SLI Bridge to try to see if it would work in the mean time.

 

[marcusmarcula]

Here's the Physical set-up with a comparison between the 2 HB SLI and the Nvidia SLI I was thinking of substituting in the mean time.

GTX HB SLI

Quadro HB SLI

Physical Set-up

 

[marcusmarcula]

I think you were given a faulty HB bridge after reading that the stock bridge was able to get you to SLI albeit with less power to the cards. how old is the PSU, mind you?

Just an update I moved the single stock bridge between the 2 sets of fingers to see if it picked up the same error message. It turns out It did not display the error message when the bridge was connected to the 2nd set of fingers, so perhaps the GPU fingers are faulty on one of the Quadros, not sure but that's my best guess since I would think it should display the same error on both fins when attached regardless...

SLI in first slot

Message when in slot one

SLI in second slot

No Message when plugged into second slot